re PR tree-optimization/83075 (Invalid strncpy optimization)

	PR tree-optimization/83075
	* gcc.dg/tree-ssa/strncpy-2.c: Use size_t instead of unsigned, add
	separate function with noipa attribute to also verify behavior when
	optimizers don't know the sizes and aliasing, verify resulting sizes
	and array content.  Add -Wstringop-overflow to dg-options.
	* gcc.dg/tree-ssa/strncat.c: Likewise.

From-SVN: r255485

3 files changed, 65 insertions, 24 deletions

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 9f8e837..d4cb0d2 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,12 @@
+2017-12-08  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/83075
+	* gcc.dg/tree-ssa/strncpy-2.c: Use size_t instead of unsigned, add
+	separate function with noipa attribute to also verify behavior when
+	optimizers don't know the sizes and aliasing, verify resulting sizes
+	and array content.  Add -Wstringop-overflow to dg-options.
+	* gcc.dg/tree-ssa/strncat.c: Likewise.
+
 2017-12-07  Thomas Preud'homme  <thomas.preudhomme@arm.com>
 
 	* lib/target-supports.exp (check_effective_target_fstack_protector):
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/strncat.c b/gcc/testsuite/gcc.dg/tree-ssa/strncat.c
index 93a60c8..9b8cf23 100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/strncat.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/strncat.c
@@ -1,19 +1,35 @@
-/* PR tree-optimization/83075 - Invalid strncpy optimization
-   { dg-do run }
-   { dg-options "-O2 -Wno-stringop-overflow" } */
+/* PR tree-optimization/83075 - Invalid strncpy optimization */
+/* { dg-do run } */
+/* { dg-options "-O2 -Wstringop-overflow" } */
 
-int main (void)
+typedef __SIZE_TYPE__ size_t;
+
+__attribute__((noipa)) size_t
+foo (char *p, char *q, size_t *r)
 {
-  char a[8] = "";
+  size_t n0 = __builtin_strlen (p);
+  __builtin_strncat (q, p, n0);		/* { dg-warning "specified bound depends on the length" } */
+  size_t n1 = __builtin_strlen (p);
+  *r = n0;
+  return n1;
+}
 
+int
+main ()
+{
+  char a[8] = "";
   __builtin_strcpy (a, "123");
-
-  unsigned n0 = __builtin_strlen (a);
-
-  __builtin_strncat (a + 3, a, n0);
-
-  unsigned n1 = __builtin_strlen (a);
-
+  size_t n0 = __builtin_strlen (a);
+  __builtin_strncat (a + 3, a, n0);	/* { dg-warning "specified bound depends on the length" } */
+  size_t n1 = __builtin_strlen (a);
   if (n1 == n0)
     __builtin_abort ();
+  a[6] = '7';
+  __builtin_strcpy (a, "456");
+  size_t n2;
+  if (foo (a, a + 3, &n2) != 6 || n2 != 3)
+    __builtin_abort ();
+  if (__builtin_memcmp (a, "456456\0", sizeof "456456\0"))
+    __builtin_abort ();
+  return 0;
 }
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/strncpy-2.c b/gcc/testsuite/gcc.dg/tree-ssa/strncpy-2.c
index 42203d5..2ef9cd6 100644
--- a/gcc/testsuite/gcc.dg/tree-ssa/strncpy-2.c
+++ b/gcc/testsuite/gcc.dg/tree-ssa/strncpy-2.c
@@ -1,19 +1,35 @@
-/* PR tree-optimization/83075 - Invalid strncpy optimization
-   { dg-do run }
-   { dg-options "-O2 -Wno-stringop-overflow" } */
+/* PR tree-optimization/83075 - Invalid strncpy optimization */
+/* { dg-do run } */
+/* { dg-options "-O2 -Wstringop-overflow" } */
 
-int main (void)
+typedef __SIZE_TYPE__ size_t;
+
+__attribute__((noipa)) size_t
+foo (char *p, char *q, size_t *r)
 {
-  char a[8] = "";
+  size_t n0 = __builtin_strlen (p);
+  __builtin_strncpy (q, p, n0);		/* { dg-warning "specified bound depends on the length" } */
+  size_t n1 = __builtin_strlen (p);
+  *r = n0;
+  return n1;
+}
 
+int
+main ()
+{
+  char a[8] = "";
   __builtin_strcpy (a, "123");
-
-  unsigned n0 = __builtin_strlen (a);
-
-  __builtin_strncpy (a + 3, a, n0);
-
-  unsigned n1 = __builtin_strlen (a);
-
+  size_t n0 = __builtin_strlen (a);
+  __builtin_strncpy (a + 3, a, n0);	/* { dg-warning "specified bound depends on the length" } */
+  size_t n1 = __builtin_strlen (a);
   if (n1 == n0)
     __builtin_abort ();
+  a[6] = '7';
+  __builtin_strcpy (a, "456");
+  size_t n2;
+  if (foo (a, a + 3, &n2) != 7 || n2 != 3)
+    __builtin_abort ();
+  if (__builtin_memcmp (a, "4564567", sizeof "4564567"))
+    __builtin_abort ();
+  return 0;
 }